<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<title></title>
		<style>
			.msg{
				width: 500px;
				padding: 10px;
				border: 1px solid black;
				display: none;
			}
		</style>
	</head>
	<body>
		<input type="checkbox" onmouseover="oDiv.style.display = 'block'" onmouseout="oDiv.style.display = 'none'">
		<div id="oDiv" class="msg">
			安全
		</div>
	</body>
</html>
